A heat advisory will take effect across St. Croix, St. Thomas and St. John at 10 a.m. Sunday, Oct. 4, as the National Weather Service warns of conditions that could cause heat-related illness, particularly among people without adequate cooling or hydration. The advisory runs through 4 p.m. AST.
Issued by the weather service’s San Juan office at 2:25 a.m., the advisory also covers adjacent islands and Puerto Rico. Forecasters identified coastal areas, lowlands, interior valleys and urban areas as locations where the health risks are greatest, and warned that high temperatures or elevated heat indices can worsen symptoms in people with chronic conditions.
Sunday’s forecast calls for highs around 96°F on St. Croix and 94°F on St. Thomas and St. John. Those figures represent forecast air temperatures. The advisory does not provide a numerical heat-index forecast, which describes how hot conditions feel when humidity is factored into the air temperature.
Scattered showers and isolated afternoon thunderstorms are also forecast, with a 50 percent chance of rain in both island forecast zones and east winds of 10 to 15 mph. In its early-morning forecast discussion, the weather service said heat would remain a concern before afternoon rain develops and in areas where rainfall remains limited.
The agency’s heat-safety guidance identifies young children, older adults, pregnant women and people with chronic medical conditions as particularly vulnerable. Outdoor workers also face increased exposure, making access to drinking water, shade and cooling breaks important for those spending extended periods outside.
Residents are advised to drink water regularly, spend time in air-conditioned locations when possible and reduce direct sun exposure. Strenuous activities should be moved to cooler parts of the day, and lightweight, loose-fitting clothing can help reduce heat stress. People whose medical care includes restrictions on fluid intake should consult their clinician before increasing how much they drink.
The weather service also recommends checking on relatives and neighbors who may need help staying cool, particularly older adults and people who are sick or have limited mobility. Children should never be left unattended in vehicles, even briefly or with windows lowered.
Heat exhaustion can cause heavy sweating, weakness, dizziness, headache, nausea or fainting. The weather service advises moving an affected person to a cooler place, loosening clothing and using cool, wet cloths; immediate medical attention is needed if the person vomits, symptoms worsen or they last longer than an hour. Confusion, slurred speech or loss of consciousness can indicate heat stroke, a medical emergency requiring an immediate 911 call and efforts to cool the person while help arrives.
Forecasters said heat concerns could continue into early next week. Residents and visitors should monitor subsequent weather service updates for changes to Sunday’s advisory or additional heat alerts.
